System and method for reducing latency during data transmissions over a network

ABSTRACT

A system and method is provided whereby more data packets than are necessary may be transmitted in order to prompt a node of network to more quickly increase the number of packets that will be accepted by the node. In one aspect, a single packet of data is split into multiple packets. In another aspect, a single packet of data is padded so that multiple packets need to be sent.

CROSS-REFERENCE TO RELATED APPLICATION

The present application is a continuation of U.S. patent applicationSer. No. 13/667,248, filed on Nov. 2, 2012, which is a divisional ofU.S. patent application Ser. No. 12/706,308, filed on Feb. 16, 2010, nowU.S. Pat. No. 8,325,623, the entire disclosures of which areincorporated herein by reference.

BACKGROUND OF THE INVENTION

The Internet protocol suite is a well known and widely used suite ofprotocols for servicing data transmissions between two devicescommunicating information over the Internet. In particular, theTransmission Control Protocol or TCP is a part of the Internet protocolsuite that provides for connection-oriented, reliable, and ordereddelivery of a stream of information (i.e., payload data) between, forexample, a web-browser application running on a client device and aweb-server application running on a server device over a local or widearea network.

To communicate with a server device using the TCP protocol, a clientdevice must first establish a TCP connection with the server. After aTCP connection is established, each device may transmit information tothe other device in a sequence of discrete data packets, where each datapacket contains a header portion and a data portion.

To ensure efficient communication, the TCP protocol incorporates severalmechanisms that determine the amount of data (e.g., bytes) that may betransmitted in a single data packet, the flow or rate at which multiplepackets are exchanged between the devices, and the effect of the packettransmissions on overall network congestion.

For example, the maximum amount of payload data that a sending devicemay transmit in the data portion of a single data packet to a receivingdevice is governed by the maximum segment size (“MSS”) value. Byconvention, the default MSS value is typically understood to be1430-1460 bytes, but a larger or smaller MSS value may be set by thereceiving device (based on its capabilities to receive a larger orsmaller amount of data from the sending device in a single packet) andcommunicated to the sending device during the initial process ofestablishing the TCP connection. Once the MSS value is established, asending device may not transmit a data packet where the data portion ofthe packet contains an amount of payload data exceeding the MSS value ofthe receiving device.

Another mechanism provided by the TCP/IP protocol to ensure reliablecommunication between two devices communicating over the network inaccordance with the protocol is the acknowledgement mechanism, whereeach device acknowledges the reception of data received from the otherdevice. For efficiency and in order to reduce network congestion, thereceiving device typically does not send a separate acknowledgement foreach data packet that it receives from the sending device. Rather, theacknowledgement mechanism of the TCP protocol is conventionallyimplemented such that the receiving device will delay transmitting anacknowledgment until it receives at least two data packets from thesending device. The delayed acknowledgement, when transmitted, typicallyacknowledges the reception of the data contained in two consecutivepackets.

A sending device can often fit all of its data into a single packet, inwhich case it has only one packet to send. Accordingly, if the receivingdevice receives the first packet but does not receive a second packet,the receiving device will send an acknowledgement indicating thereception of the first packet after waiting for a prescribed amount oftime (typically around 200 ms) for the second packet to arrive.

If the data acknowledged by the receiving device does not match the datathat was transmitted (for example, if the receiving device onlyacknowledges the data in one packet when two data packets weretransmitted by the server), the sending device retransmits theunacknowledged data packet to the receiving device, until alltransmitted data is successfully acknowledged by the receiving device.Furthermore, if the sending device does not receive an acknowledgementwithin a prescribed period of time (because, for example, the client'sacknowledgement packet is lost in transmission, or because none of thedata packets transmitted by the server were received at the clientdevice), the sending device retransmits unacknowledged data packets tothe receiving device after waiting for an acknowledgement for aprescribed amount of time. The amount of time that the sending devicewaits prior to retransmitting the unacknowledged data packet isdynamically determined by the sending device based on estimated networkconditions.

The mechanism known as the congestion window (“CW”) is another aspect ofthe TCP protocol that is designed to increase efficiency. Rather thandefining the maximum size of the packet, the CW defines the maximumamount of data that a sending device (e.g., a server) may transmit atany given time to a receiving device (e.g., a client) before having towait for an authorization from the receiving device to send more. Inthis regard, the CW comprises the maximum number of unacknowledgedpackets that a sending device may transmit to a receiving device inseries prior to having to wait for an acknowledgement from the receivingdevice, where the maximum amount of data contained in each of thetransmitted packets is based upon the MSS value of the receiving device.

In particular, some conventional implementations of the TCP/IP protocolset the CW to an initial default value of two (2) packets. Thus, asending device may initially send two unacknowledged data packets to areceiving device and then must wait for an acknowledgement of thosepackets prior to sending any remaining packets. Upon receiving anacknowledgement for the initial two packets, the sending device mayincrease the value CW and transmit a larger number of the remainingpackets in series prior to having to again wait for anotheracknowledgement from the receiving device.

The value of CW is typically increased by the number of packets that areacknowledged. Thus, for example, once the server receives anacknowledgement indicating the reception of the initial two packets, theserver may increase the initial CW value (2 packets) by the number ofacknowledged packets (2 packets), resulting in a new CW value of four(4) packets. Consequently, the server may now transmit four packets in asequence to the client prior to having to wait for anotheracknowledgment.

The process of increasing the value of CW by the number of theacknowledged packets can theoretically continue indefinitely, until allavailable payload data has been successfully transmitted from thesending device to the receiving device. In the event that the sendingdevice determines that one or more transmitted packets have been lost(i.e., because the transmitted packets have not been acknowledged by thereceiving device within a prescribed period of time or because anegative acknowledgement is received), the value of CW is conventionallyreduced by half (attributing the loss to congestion on the network) andthe unacknowledged packets are retransmitted by the sending device inaccordance with the reduced value of CW.

BRIEF SUMMARY OF THE INVENTION

In one aspect, a method of transmitting packets over a network isprovided. The method includes: receiving first data to be transmittedvia the network to a client device; determining a first value with aprocessor, the first value based upon a number of data packets that willbe acknowledged by the client device prior to receiving additionalpackets; determining a second value with the processor, where the secondvalue is based upon a maximum data size of a data packet; determining,based on the first and second values, whether the minimum number of datapackets necessary to transmit the first data to the client device isless than the first value; transmitting, based on the determination thatthe minimum number data packets necessary to transmit the first data isless than the first value, the first data to the client device in aplurality of data packets greater than or equal to the first value viathe network.

In another aspect, a system is provided that includes a memory storinginstructions and data, the data comprising first data to be transmittedover a network to a client device; and a processor to execute theinstructions and to process the data. The instructions include:receiving first data to be transmitted via the network to a clientdevice; determining a first value with a processor, the first valuebased upon a number of data packets that will be acknowledged by theclient device prior to receiving additional packets; determining asecond value with the processor, where the second value is based upon amaximum data size of a data packet; determining, based on the first andsecond values, whether the minimum number of data packets necessary totransmit the first data to the client device is less than the firstvalue; transmitting, based on the determination that the minimum numberdata packets necessary to transmit the first data is less than the firstvalue, the first data to the client device in a plurality of datapackets greater than or equal to the first value via the network.

In a yet another aspect, a method for transmitting data is provided, themethod including: receiving first payload data to be transmitted from afirst node to a second node via a network, the first payload data havinga size less than the maximum amount of payload data that will beaccepted by the second node in a single data packet; and transmitting,from the first node to the second node via the network, a first datapacket and a second data packet, where each of the first data packet andthe second data packet include a portion of the first payload data.

In a yet another aspect, A method for transmitting data is provided, themethod including: receiving first payload data to be transmitted via anetwork from a first node to a second node, determining whether thefirst payload data has a size less than the maximum amount of payloaddata that will be accepted by the second node in a single data packet;providing padding data based on the determining, where padding dataincludes data not intended to be discernable by a user associated withthe second node; and transmitting, from the first node to the secondnode via the network, a first data packet and a second data packet,where at least one of the packets contains the first payload data andwhere at least one of packets contains the padding data.

In a further aspect, a system is provided, the system including: a firstdevice at a first node of a network, the first device including a firstmemory storing a first set of instructions and a first processor thatprocesses data in accordance with the first set of instructions; asecond device at a second node of the network, the second computercomprising a second memory storing a second set of instructions and asecond processor that processes data in accordance with the second setof instructions; the first device having access to first data to betransmitted over the network to the second device. Wherein, the firstset of instructions include: receiving first data to be transmitted viathe network to a client device; determining a first value, the firstvalue based upon a number of data packets that will be acknowledged bythe client device prior to receiving additional packets; determining asecond value, where the second value is based upon a maximum data sizeof a data packet; determining, based on the first and second values,whether the minimum number of data packets necessary to transmit thefirst data to the client device is less than the first value;transmitting, based on the determination that the minimum number datapackets necessary to transmit the first data is less than the firstvalue, the first data to the client device in a plurality of datapackets greater than or equal to the first value via the network. Andwherein the second set of instructions include: receiving the pluralityof packets transmitted by the first device via the network; transmittingan indication via the network to the first device that additional datamay be sent; and displaying the first data to a user on a display.

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects and advantages of the present invention will be apparentfrom the following detailed description of the present preferredembodiments, which description should be considered in conjunction withthe accompanying drawings in which like reference indicate similarelements and in which:

FIG. 1 is a block diagram of an exemplary embodiment of the system ofFIG. 2.

FIG. 2 is a block diagram of a system in accordance with an aspect ofthe present invention.

FIGS. 3-10 illustrate an exemplary operation in accordance with oneaspect of the present invention.

FIGS. 11-13 illustrates an exemplary operation in accordance withanother aspect of the present invention.

FIG. 14-15 is a flow diagram of a process in accordance with one aspectof the present invention.

FIG. 16 is a flow diagram of a process in accordance with another aspectof the present invention.

FIG. 17 is a flow diagram of a process in accordance with variousaspects of the present invention.

DETAILED DESCRIPTION

In one aspect, a system and method is provided whereby latency between asending device and receiving device, such as but not limited to a serverand a client exchanging information over a network, is reduced bysplitting data that may be transmitted to the receiving device in asingle data packet into multiple smaller data packets, so as to inducethe receiving device to send an acknowledgment earlier than it would ifonly a single data packet was transmitted.

Referring to FIGS. 1-2, a communication system 100 in accordance withone aspect of the invention may provide for exchange of data between aclient computer 12 and a server computer 50 over a communication network60. The client computer 12 contains a processor 20, memory 22 and othercomponents typically present in general purpose computers. In addition,the server 50 contains a processor 70 and a memory 72.

The memory 22 stores information accessible by the processor 20,including instructions 24 that may be executed by the processor 20 anddata 26 that may be retrieved, manipulated or stored by the processor20. Similarly, the memory 72 stores information accessible by processor70, including instructions 76 that may be executed by the processor 70and data 74 that may be retrieved, manipulated or stored by theprocessor 70. The memory may be of any type capable of storinginformation accessible by the processor, such as a hard-drive, memorycard, ROM, RAM, DVD, CD-ROM, write-capable, read-only memories.

The processors 20, 70 may comprise any number of well known processors,such as processors from Intel Corporation. Alternatively, the processorsmay be a dedicated controller such as an ASIC.

The instructions 24, 76 may comprise any set of instructions to beexecuted directly (such as machine code) or indirectly (such as scripts)by the processors 20, 70, respectively. In that regard, the terms“instructions,” “steps” and “programs” may be used interchangeablyherein. The instructions may be stored in object code form for directprocessing by the processor, or in any other computer language includingscripts or collections of independent source code modules that areinterpreted on demand or compiled in advance. The functions, methods androutines of instructions in accordance with the present invention areexplained in more detail below.

The data 26, 74 may be retrieved, stored or modified by the processors20, 70 in accordance with the instructions 24, 76, respectively. Thedata may be stored as a collection of data. For instance, although theinvention is not limited by any particular data structure, the data maybe stored in computer registers, in a relational database as a tablehaving a plurality of different fields and records, XML documents, orflat files. The data may also be formatted in any computer readableformat such as, but not limited to, binary values, ASCII or EBCDIC(Extended Binary-Coded Decimal Interchange Code). Moreover, the data maycomprise any information sufficient to identify the relevantinformation, such as descriptive text, proprietary codes, pointers,references to data stored in other memories (including other networklocations) or information which is used by a function to calculate therelevant data.

Although the processor and memory are functionally illustrated in FIG. 2within the same block, it will be understood by those of ordinary skillin the art that the processor and memory may actually comprise multipleprocessors and memories that may or may not be stored within the samephysical housing. For example, some of the instructions and data may bestored on removable CD-ROM and others within a read-only computer chip.Some or all of the instructions and data may be stored in a locationphysically remote from, yet still accessible by, the processor.Similarly, the processor may actually comprise a collection ofprocessors which may or may not operate in parallel.

In one embodiment, the client computer 12 may be a general purposecomputer, intended for use by a person, having all the internalcomponents normally found in a personal computer such as a centralprocessing unit (CPU), display 30, input 32 such as a CD-ROM drive,mouse, keyboard or microphone, and a hard-drive, speakers, modem and/orrouter (telephone, cable or otherwise) and all of the components usedfor connecting these elements to one another. Moreover, computers 50, 12in accordance with the systems and methods described herein may compriseany device capable of processing instructions and transmitting data toand from humans and other computers, including network computers lackinglocal storage capability, PDAs with modems and Internet-capable wirelessphones. Although the only input means shown in FIG. 1 are the mouse andkeyboard, other means for inputting information from a human into acomputer are also acceptable such as a microphone, touch-sensitivescreen, voice recognition, position or orientation sensitive devicesincluding accelerometers, etc.

The server 50 and the client computer 12 are capable of direct andindirect communication, such as over the network 60. Although only asingle client computer and a single server are depicted in FIGS. 1 and2, it should be appreciated that a typical system can include a largenumber of connected computers and several servers to which the computerscan connect, with each different computer being at a different node ofthe network. The network, and intervening nodes, may comprise variousconfigurations and protocols including the Internet, intranets, virtualprivate networks, wide area networks, local networks, private networksusing communication protocols proprietary to one or more companies,Ethernet, WiFi and HTTP. Such communication may be facilitated by anydevice capable of transmitting data to and from other computers, such asmodems (e.g., dial-up or cable), networks cards and wireless interfaces.

In accordance with one aspect of the invention, instructions 76 inserver 50 may include a search engine 78 application and communicationroutines 80. The search engine receives search queries and generatessearch results in response, such as the search results provided byGoogle.com. While particularly advantageous when used in connection withsearch engines, it will be understood that the system and method is notlimited to any particular application.

The communication routines 80 assist in the receipt and transmission ofthe information, such as placing the results into the payload dataportion of a data packet and transmitting the results to a web-browserapplication running on the client device in accordance with the TCPcommunication protocol. In this regard, the functions of sending,receiving and processing the TCP packets may be accomplished usingcommunication routines provided by operating systems such as Linux andMicrosoft Windows.

Data 74 in the server 50 may include data 82 received from client 12over network 60. The data 82 received from client 12 may include asearch request that is input by a user into a web-browser applicationrunning on the client device and directed to the search engine runningon the server device.

Data 74 may also include data 84 to be transmitted from the serverdevice 50 to the client device 12 over network 60. The data to betransmitted from the server to the client may include padded or splitpayload data generated by the search engine in response to the searchrequest. The payload data may include, for example, webpage formattingdata and search results data generated by the search engine in responseto the search request.

Instructions 24 in client 12 may include a web-browser application 38and communication routines 40. The web-browser application 38 maycommunicate a search request, input by a user into the web-browser anddirected to the search engine running on the server, to thecommunication routines 40, which may service data transmissions betweenclient 12 and server 50 and transmit the search request to the searchengine running on the server device in accordance with the TCPcommunication protocol. The web-browser application may also format anddisplay, to the user, the payload data received from the server inresponse to the search request, as part of one or more web-pages.

The communication routines 40 assist in the receipt and transmission ofthe information from the client device to the server device. Forexample, the communication routines 40 may place the search request intothe data portions of one or more data packets and transmit the packetsto the search engine application running on the server device inaccordance with the TCP communication protocol. In this regard, thefunctions of sending, receiving and processing the TCP packets may beaccomplished using communication routines provided by operating systemssuch as Linux and Microsoft Windows.

Data 26 in the client computer 12 may include data 42 received by thecommunication routines 40 from server 50 over the network. The data 42received from the server may include padded or split payload datagenerated by the search engine running on the server in response to asearch request.

Data 26 may also include data 44 to be transmitted via the communicationroutines 40 from the client 12 to the server 50 over the network 60. Thedata 44 to be transmitted to the server may include a search requestinput by a user into the web-browser running on the client device.

An exemplary operation in accordance with the process shown in FIG. 17and various aspects of the invention follows below. It should beunderstood that the following operations do not have to be performed inthe precise order described below. Rather, various steps can be handledin reverse order or simultaneously.

In accordance with a aspect, when the size of the payload data initiallyavailable for transmission from the server to the client is less thanthe MSS value of a single data packet, the server may split and transmitthe initially available data in two data packets (even though it couldbe sent in one packet), where each of the two transmitted data packetsincludes a portion of the initially available payload data.

As indicated earlier, conventional implementation of the TCP protocolprovides for one acknowledgement for every two data packets received atthe client. In addition, the initial and default number of packets thata server may transmit to a client during the first transmission of datais typically two data packets due to the initial CW value of two (2). Bysplitting the payload data into two data packets even though all of theavailable payload data may be contained in a single data packet, theserver induces the client computer to transmit an acknowledgementearlier, because the client does not have to wait a prescribed amount oftime (typically 200 ms) for the second packet to arrive before sendingan acknowledgement.

In many cases where the amount of the initially available payload datais less than the MSS of a single packet, splitting the available payloaddata into two packets may result in a client acknowledgement beingreceived at the server relatively much earlier than it would otherwise.

For example, if only one packet was transmitted by the server containingall of the initially available data, the client will conventionally waitfor a full 200 ms of time for a second data packet before acknowledgingthe reception of the one packet, which will proportionally delay thetime at which the acknowledgement is received at the server by at leastthe same amount of time. In contrast, if the available payload data issplit into two packets, the client will acknowledge the data containedin the two packets as soon as it receives both packets, which in manycircumstances may result in the acknowledgement being receivedrelatively much earlier at the server.

The relatively earlier reception of the acknowledgement at the server,in turn, enables the server to enlarge the value of CW and to transmitthe remaining payload data, which, for a short transmission, typicallybecomes available in the meantime, relatively earlier in the subsequenttransmission.

For example, receiving an acknowledgement for the first two packets 100ms earlier than it would be received if only a single data packet wastransmitted enables the server to increase the value of CW from two (2)to four (4) and transmit four data packets 100 ms earlier, where, intypical short transmissions, the four transmitted packets may containall of the remaining portion of payload data responsive to a searchrequest from the client. In contrast, if only a single packet had beentransmitted initially, the server would have to wait at least 200 msbefore it could send all of the same four packets, resulting in anoverall larger latency. Thus, by inducing the client to sendacknowledgements earlier when transmissions are short, data packets maybe transmitted earlier from the server to the client, resulting in anoverall reduction of latency from the perspective of a user at theclient device.

FIGS. 3-10 illustrate an exemplary embodiment of a transmission inaccordance with the process of FIGS. 14-15.

At an initial time as shown in FIG. 3, client device 350 requests andreceives information from server 310. For example, a user may use abrowser 360 executed by client device 350 to log into a web site hostedby server 310 in order to transmit a search query 380 to the server'ssearch engine 330 via web pages provided by the server. As shown by thedotted lines, the search query may be provided to the search engine 330with the assistance of the communication routines 330.

In accordance with TCP/IP protocol, the server 310 and client device 350may have already established values (shown as TCP data 340) indicatingthat the server side MSS value is 1460 bytes, and the CW value isinitially set to 2.

As shown in FIG. 4, the search engine 330 may generate initial results410 responsive to search query 380 for display to the user on a web pageand pass the results to the communication routines 320 for transmissionbefore the remainder of the page is ready. For example, the initialresults 410 may include information that can be transmitted quicklybecause it is completely or mostly independent of the user's query suchas text and images that are always present at the top or bottom of theweb page sent to the user. Instead or in addition, the initial resultsmay include the first search results retrieved in response to the query,such as sponsored ads or non-sponsored results. It will be assumed forthe purposes of the example that the initial results are less than theMSS, namely, the initial results are 1000 bytes compared to the MSSvalue of 1460 bytes.

In a typical prior art system and method operating in accordance withTCP/IP protocol, communication routines would parse the initial resultsinto the least number of required packets. For example, in such a systemand method, the initial results 410 may be sent immediately to theclient device in a single packet because it is small enough to fit in asingle packet. As a result of sending only one packet the client devicewill not acknowledge the packet before waiting for a prescribed amountof time for a second packet thus delaying or stalling the server devicefrom increasing the congestion window.

In accordance with one aspect of the present system and method, theserver determines whether the initial results would fit within a singlepacket and, if so, splits the initial results into multiple packets eachcontaining a different portion of the results. For example, as shown inFIG. 5, the server 310 splits the initial results 410 into two packets510 and 511, each of which contains a different half of the resultsdata. In this regard, it will be understood that the present inventionis not limited to splitting the results into multiple packets eachcontaining an equal portion of the results, and that the multiplepackets may contain different amounts of the results without departingfrom the scope of the invention.

As shown in FIG. 6, the server 310 transmits the two packets 510-11 toclient device 350. Because the client device has now received twopackets, it will transmit an acknowledgment 610 to server 310 withoutwaiting for any additional packets. In response to receiving theacknowledgement for packets 510-11, server 310 increases the value ofthe congestion window 620 from “2” to “4”, i.e., the server may nowtransmit up to four packets to the client without waiting for anotheracknowledgement.

As shown in FIG. 7, the client may display both halves 510-511 of theinitial results (i.e., all of the initial results 410) on the display370 while awaiting additional results from the server.

As shown in FIG. 8, the search engine 330 provides additional results810 to communication routines 320 for transmission in response to theclient device's original request. It will be assumed for the purposes ofthe example that the additional results are substantially greater thanthe MSS, namely, the additional results are 5000 bytes compared to theMSS value of 1460 bytes. Accordingly, as shown in FIG. 9, thecommunication routines 320 split the data into individual packets911-914 sized to fit with the maximum packet size.

As shown in FIG. 10, the packets 911-914 of additional results aretransmitted to the client device 350, which displays the additionalresults 810 along with the initial results 410 on the display 370. Inresponse to receiving packets 911-914, client device 350 will transmitacknowledgements 1020-21 to the server device 310. In response toreceiving acknowledgements 1020-21, server 310 may further increase thecongestion window (such as by increasing the CW from four (4) to eight(8) as shown at reference number 1030).

Accordingly, by splitting the initial payload data into multiple packetswhen the server may have instead sent the entire payload in a singlepacket, the server in many cases facilitates an earlier transmission ofan acknowledgement from the client, which allows the server to enlargethe congestion window and send the remaining portions of the payloaddata to the client at an earlier time.

In another aspect, the system and method will continue to determine theamount of packets required to induce the client device to sendacknowledgements earlier than if the packets are sent at their maximumsize. For example, if the size of the additional results in FIG. 9 was1000 bytes (less than the MSS of 1460 bytes), the additional results maybe split into two packets sized at 500 bytes each (thus inducing theclient to send one acknowledgement in response), or even four packetssized at 250 bytes each (thus inducing the client to send twoacknowledgements in response).

In another aspect of the system and method, instead of splitting theinitially available payload data into two packets where the size of theinitially available payload data is less than the MSS value of a singledata packet, the server may instead append additional non-payload datato the payload data, where the non-payload data is data that is notrequested by the client and is unrelated to the search request. Theamount of the non-payload data that is appended to the payload data maybe such that the total amount of the payload data and the non-payloaddata together exceeds the MSS value of a single data packet, but is lessthan or equal to the combined MSS value of two data packets. The servermay then transmit two data packets to the client as before, but ratherthan splitting the payload data into two packets, in this case the firstdata packet includes all of the initially available payload data and aportion of the appended non-payload data, and the second data packetonly includes the remaining portion of the appended non-payload data.

FIGS. 11-14 provide an example of this aspect of the system and methodin accordance with the process of FIG. 16. TCP/IP Routines 1120 maycomprise communication routines, such as those present in certainexisting operating systems that are preconfigured to use as few packetsas possible to transmit data in accordance with TCP/IP protocol. Paddingroutine 1125 may comprise instructions that process data from the searchengine 330 prior to it being provided to the TCP/IP Routines.

As shown in FIG. 11 and by way of example, padding routine 1125 receivesinitial search results 1130 from the search engine 330 such that thesearch results are small enough (e.g., 1000 bytes) to be transmitted ina single packet.

Because the initial results are small enough to be sent as a singlepacket, the server' padding routine 1125 may append information to theresults until it is too large to fit within a single packet. As shown inFIG. 12, for example, server 310 may append padding data 1240 to theinitial results 1130 to create padded results 1250. In one aspect of thesystem and method, the padding data comprises data that will be eitherremoved by the client device prior to display or information that isdifficult for a user to discern—or otherwise meaningless to the user ifdiscerned—when displayed (by way of example only, null characters, spacecharacters, pictures having 0 pixels, HTML header data, etc.). Forexample, if the initial results were 1000 bytes and the MSS was 1460bytes, the server may append 461 bytes of null characters so that thecombined results exceed the MSS.

As shown in FIG. 13, the padded results 1250 are sent to the TCP/IProutines 1120, which packetize different portions of the padded resultsinto two packets 1311-12 (because the size of the padded data exceedsthe MSS of 1460). The server then transmits both packets to the clientdevice 350, which displays the padded results to the user on display370. As noted above, the padding may be selected so as to be essentiallyinvisible to the user, in which case displaying the padded resultscauses the initial results 1130 be readily discernable to the userwhereas the padding 1240 is not.

As before, based on receipt of the packets 1311 and 1312, the clientcomputer 350 will transmit an acknowledgement acknowledging thereception of the data contained in the two transmitted packets. As aresult, the server 310 increases the value of congestion window by thenumber of acknowledged packets. Appending additional data to the initialpayload data thus enables the server to send more packets to the clientdevice before waiting for another acknowledgment from the client device.Accordingly, in this aspect of the system and method, increasing thesize of the requested data may actually reduce the latency fortransmission and reception of the overall dataset.

FIG. 17 shows a process in accordance with various aspects of theinvention. As shown therein, a sending device, such as, for example, aserver, may receive information to be provided to a client device over,for example, a network. The sending device may determine the size of theinformation, and may also determine the minimum number of packetsnecessary to transmit the information to the client device, where theminimum number of packets is determined based on the maximum size ofdata that may be included in each of the minimum number of packets.After determining the minimum number of packets required, the sendingdevice may also determine if any additional or remaining number ofpackets may be transmitted to the client in order to induce the clientinto sending an acknowledgement earlier, that is, without waiting toreceive any more packets. If so, the sending device may increase thenumber of packets to be transmitted to the client device by theadditional or remaining number of packets by either splitting or paddingthe information to be transmitted as disclosed herein above. The sendingdevice may then transmit the information to the client by transmittingthe increased number packets over the network. After the increasednumber of packets are transmitted to the client, the sending device andmay receive one or more indications from the client that acknowledge thereception of the transmitted packets. Subsequent to receiving the one ormore indications, the sending device may increase the maximum number ofpackets that may be transmitted to the client device by the number ofthe acknowledged packets in a subsequent transmission of information tothe client device.

The aspects of the invention disclosed herein have the advantage ofbeing flexible enough to accommodate a variety of alternatives. Forexample, the splitting or padding of data may be performed by the searchengine, by the operating system or another routine on the sendingdevice.

Yet further, the system and method may be used with client devices thatoperate in accordance with conventional implementations of the TCP/IPprotocol. For example and in one aspect, the client device providesacknowledgements and permits increases in the size of the congestionwindow without determining (or without receiving any informationindicating) that the packets were split or padded by the server. Inanother aspect, the client device implements routines that complementthe actions of the server, such as searching for and removing paddingdata added by the server.

Although the invention herein has been described with reference toparticular embodiments, it is to be understood that these embodimentsare merely illustrative of the principles and applications of thepresent invention. It is therefore to be understood that numerousmodifications may be made to the illustrative embodiments and that otherarrangements may be devised without departing from the spirit and scopeof the present invention as defined by the appended claims.

The invention claimed is:
 1. A method comprising: accessing data to besent to a receiving device, determining, with one or more processors, afirst number of packets based on the size of the data to be sent and apacket size, determining, with one or more processors, a second numberof packets that, when received by the receiving device, will prompt thereceiving device to acknowledge the packets without waiting an amount oftime, sending the data in at least a first number of packets when thefirst number is greater than the second number, and sending the data inat least a second number of packets when the second number is greaterthan the first number, wherein sending the data in at least a secondnumber of packets comprises sending the data in a set of packets suchthat at least one packet in the set contains at least a portion of thedata to be sent and at least one packet does not contain a portion ofthe data to be sent.
 2. The method of claim 1 further comprising paddingthe data before sending the data when the second number is greater thanthe first number.
 3. The method of claim 2 wherein padding the datacomprises padding the data to be sent with data that is not intended tobe discernable by a user.
 4. The method of claim 1, wherein determiningthe first number comprises determining the first number based on thesize of the data to be sent and the maximum size of a packet set by atransmission protocol.
 5. The method of claim 1, wherein the sendingdevice transmits data over the network in accordance with TCP protocol.6. The method of claim 1, wherein sending the data in at least the firstnumber of packets includes splitting the data to be sent into at least afirst portion and a second portion, storing the first portion in a firstpacket of the set, and storing the second portion in a second packet ofthe set.
 7. The method of claim 6, wherein a combined size of the firstportion and the second portion is less than an amount of payload datastorable in a single packet in accordance with the protocol.
 8. Anon-transitory computer-readable medium storing a set of instructions,which when executed by one or more processors causes the one or moreprocessor to perform a method comprising: accessing data to be sent to areceiving device, determining, with one or more processors, a firstnumber of packets based on the size of the data to be sent and a packetsize, determining, with one or more processors, a second number ofpackets that, when received by the receiving device, will prompt thereceiving device to acknowledge the packets without waiting an amount oftime, sending the data in at least a first number of packets when thefirst number is greater than the second number, and sending the data inat least a second number of packets when the second number is greaterthan the first number, wherein sending the data in at least a secondnumber of packets comprises sending the data in a set of packets suchthat at least one packet in the set contains at least a portion of thedata to be sent and at least one packet does not contain a portion ofthe data to be sent.
 9. The medium of claim 8, wherein the methodfurther comprises padding the data before sending the data when thesecond number is greater than the first number.
 10. The medium of claim9, wherein padding the data comprises padding the data to be sent withdata that is not intended to be discernable by a user.
 11. The medium ofclaim 8, wherein determining the first number comprises determining thefirst number based on the size of the data to be sent and the maximumsize of a packet set by a transmission protocol.
 12. The medium of claim8, wherein sending the data in at least the first number of packetsincludes splitting the data to be sent into at least a first portion anda second portion, storing the first portion in a first packet of theset, and storing the second portion in a second packet of the set. 13.The medium of claim 12, wherein a combined size of the first portion andthe second portion is less than an amount of payload data storable in asingle packet in accordance with the protocol.